The present invention relates to the harvesting of flue cured tobacco and, more specifically, to a tobacco harvester which separates the upper leaves from the lower leaves in a single pass of the harvester through the field. This harvester is an improvement over the harvester disclosed in U.S. Pat. No. 6,185,921, issued Feb. 13, 2001 and assigned to the assignee hereof, the disclosure of which patent is incorporated herein by reference.
Tobacco harvesting methods have changed in recent years. Previously, tobacco leaves were harvested progressively as they ripened from the bottom of the plant upward over the course of the ripening season. The harvesting was accomplished on a series of passes through the field to select only the leaves that were ripe, initially a manual harvesting with the leaf selection accomplished visually, and more recently mechanically with the leaf selection accomplished by an adjustment of the height at which the leaves were stripped form the stalk.
The simultaneous mechanical harvest of most if not all of the tobacco leaves is now favored because of the cost of labor, the development of tobacco plants whose leaves ripen during a narrower time span and the availability of chemical ripeners. If the leaves are harvested in one pass through the field, the leaves thereafter must be sorted by quality, generally a function of the location of the leaf on the stalk.
Burley tobacco is harvested by cutting the entire stalk and curing the leaves by air drying while attached to the stalk. It is know to sort the leaves of cured burley tobacco as they are stripped from the stalk and such a tobacco leaf-stripping device is disclosed, for example, in U.S. Pat. No. 4,282,888 dated Aug. 11, 1981, U.S. Pat. No. 4,773,434 dated Sep. 27, 1988, and U.S. Pat. No. 4,836,220 dated Jun. 6, 1989. Such devices are not adaptable for the harvesting of flue cured tobacco in the field, nor are they adapted for use with uncured tobacco leaves.
Accordingly, it is an object of the present invention to provide a novel tobacco harvester and method for selectively removing in a single pass through the field leaves from two different areas on the tobacco stalk as a function of the height at which they grow in the stalk.
These and many other objects and advantages of the present invention will be readily apparent to one skilled in the art to which the invention pertains from a perusal of the claims, the appended drawings, and the following detailed description of the preferred embodiments.